It is global warming! (maybe not as I read your update)At least your tomato plants have fruited tomatoes... mine are just leafy green plants that appear to have no clue what they are supposed to produce.
What you need to do is start pruning the vines as the growing season is on the way out. Remove any leaves that are shading the fruit, pinch out any buds that are developing and remove some of the lower leaves. You want to force all the energy of the plant into the fruit you have left on the vine. Please don't overprune as the plant still needs to do its photosynthesis thing.You can pick the green tomatoes and ripen them on the windowsill but from memory they will not get any sweeter so they could make the face pucker a tad. Or you could make green tomato chutney?
Thanks Pique Oil, going through my john Seymour books I came across very similar instructions. We live and learn, a better crop promises next season!